Reproductive biology of an invasive population of European green crab, Carcinus maenas, in Placentia Bay, Newfoundland

The European green crab, Carcinus maenas, was initially discovered in North Harbour, Placentia Bay, Newfoundland in 2007. Reproductive biology of this sub-arctic population was investigated and compared to populations in other areas of Atlantic Canada where invasions have occurred in recent decades in different environments. Histological and gonadosomatic carapace width value (GCW) analyses showed that male green crab are mature at carapace width (CW) 32 mm and females are mature at 37 mm. Placentia Bay reproductive females were smaller, spend a shorter time ovigerous, and release larvae once annually in temperatures colder than similar green crab populations in other areas of Atlantic Canada. Information on reproductive strategies in invaded areas is critical in designing mitigation and management plans to target spawning threshold levels in these green crabs.